Evaluation of the TECRA (TM) Visual Immunoassay for detecting Staphylococcus aureus in cosmetic/pharmaceutical raw materials and finished products

An assessment of the new TECRA(TM) Staphylococcus aureus Visual Immunoassay (VIA) was conducted to detect the presence of Staphylococcus aureus in cos metic/pharmaceutical raw materials and finished products. Samples were inoc ulated with pure cultures of Staphylococcus aureus. In addition, a mixed ba cterial inoculum of Staphylococcus aureus, Staphylococcus epidermidis, Esch erichia coli, and Pseudomonas aeruginosa was used to inoculate samples of r aw materials and finished products. After a 24 h incubation period at 35C, each enrichment broth was analyzed for the presence of Staphylococcus aureu s by the standard conventional method and the TECRA(TM) VIA. The following preenrichment broths were analyzed: the TECRA(TM) Staphylococcus Growth Med ium, a modified version of the TECRA(TM) Staphylococcus Growth Medium with 4% Tween 20. Tryptic Soy Broth (TSB), and TSB with 4% Tween 20. Uninoculate d enrichment broth samples were used as negative test controls. There was a 100% correlation between the visual immunoassay and the standard method in both pure and mixed culture studies for the detection of Staphylococcus au reus in preenrichment samples of the modified TECRA(TM) Staphylococcus Grow th Medium and TSB. However, the TECRA(TM) VIA detected Staphylococcus aureu s in 26 h while standard USP detection method required 4-5 days to be compl eted. These test results indicate that the TECRA(TM) Staphylococcus aureus VIA is equivalent to the conventional method for detecting the presence of Staphylococcus aureus contamination in cosmetic/pharmaceutical finished pro ducts and raw materials, but in a considerably shorter period of time. Furt hermore, the TECRA(TM) Staphylococcus aureus VIA provides a user-friendly a lternative to the standard conventional method for the detection of Staphyl ococcus aureus contamination.